Gruppe N8
What impacts could human activity have on the Neselva? The Neselva is an 11km long river that starts in Vestmarka and ends in Nesbru (Wikipedia, 2019). According to Naturvernforbundet it has the country's largest fish stocks in relation to waterflow (Naturvernforbundet). At the end of the river, there’s an old seabed which acts as a perfect spawning area for fish that migrate up the river including salmon, trout, and eel. However, this abundant breeding ground and perfect habitat for many fish are at risk from human interference. Traffic, drainage points, and construction sites threaten the health of this river ecosystem and puts one of the area’s natural resources at risk. ' One such threat comes from Neselva Hageby residential project. The municipality of Asker plans to build 1 640 housings within the area surrounding the river, along with private plots and a new bridge. They’ll work in intervals creating between 100 - 150 new housings each year and if they are able to follow that up the project is to be completed in 2035 (Utviklingen av Vestre Billingstad 10.12.2018). Even with the building process going on the municipality has stated that the river is to be safe from the construction, but have not publicly specified how it is going to be protected. ' However, they have made positive steps to ensure that its environmental impact is as low as possible; including a car sharing initiative to decrease emissions, developing a bicycle track that allows residents to bike to work and working to preserve green spaces around the municipality. Due to these projects, it seems likely that the building managers will be susceptible to integrating river conservation methods into their plans. ' Threats that DNB construction company will have to address include the fact that particles such as dust or clay fragments can be disturbed by digging into the ground and soil, which can clog the fish’s gills. Trouts instinctively seek out or return to the river they were born in to lay eggs. Therefore, if the past generation is to die, then the consequences of this can harm future generations and potentially disqualify Neselva as a reproduction site. Another issue is the potential leakage of oil or chemicals, as well as added particles in the water, which can possibly drown the fish by blocking their gills or make the spawning areas unfit for the fish. (Per Johan Færøvig, 2019).' ' The last main concern is the potential for blockage of parts of the river. Tubes and pipes used for the sewer and water system can, if placed in an inappropriate place, be a hindrance in the trout and other fish’s migration patterns up the river. This restricts the area that can be used for spawning, therefore reducing the number of trouts. In order to minimize the potential damage, one could implement regular checkups with the sewer, water and pipe systems to prevent any leakages and carry out regular maintenance on the systems. In addition, one could also enforce regular water tests whilst being careful to not disturb the reproductive cycle of the fish. The last thing that can be done is to have routine cleanups along the riverside to get rid of potential debris or objects that can interrupt the natural flow of the river. ' In summary, it is imperative that the Neselva is preserved as one of the most important fish breeding grounds in the area. With cooperation from the corporation in charge of building the municipality and an obvious effort to conserve the river when considering new developments and human activity along the river, the Neselva can continue to support marine life and provide bountiful spawning areas to ensure that the fish in the area have a healthy population for generations to come. ' Sources: Naturvernforbundet Online Available at: https://naturvernforbundet.no/noa/import/neselva-article20590-1909.html - (Accessed: 17.12.2019) Wikipedia 14.04.2019 Neselva (Asker) Online Available at: https://no.wikipedia.org/wiki/Neselva_(Asker) - (Accessed:17.12.2019) Asker Kommune 10.12.2018 Utviklingen av Vestre Billingstad Online Available at: https://www.asker.kommune.no/samfunnsutvikling/stedsutvikling/vestre-billingstad/ - (Accessed:17.12.2019) Færøvig, Per Johan - (Personal communication 17.12.2019) ' *